Tadalafil (generic Cialis®) is used to treat erectile dysfunction (impotence or an inability to get or keep an erection) in men.¹ Tadalafil can also be used to treat premature ejaculation.²

Tadalafil is in a class of medications called phosphodiesterase (PDE) inhibitors and treats erectile dysfunction by increasing blood flow to the penis during sexual stimulation.³ This may also help treat premature ejaculation.⁴

You may be able to have sexual activity as soon as 30 minutes after taking tadalafil.⁵

When using tadalafil for erectile dysfunction, the ability to have sexual activity may be improved for up to 36 hours after taking it.⁶

Tadalafil can stay in your system up to two days after taking it.⁷

Tadalafil is prescribed in doses of 2.5 mg, 5 mg, 10 mg, 15 mg and 20 mg, with 10 mg being the most common initial dosage. Whether you are taking the medication as needed or once daily, you should not take more than one dose per day or exceed 20 milligrams in one day.⁸

Yes. When this medication is used for erectile dysfunction, your healthcare team may prescribe it to be taken once daily or as needed before sexual activity.⁹ The most common initial dosage is 10 mg, but that may be lowered based on the patient’s overall health.¹⁰

Tadalafil should not be taken more than once per day, with a maximum dosage of 20 milligrams per day.¹¹

Take this medication by mouth with a glass of water, with or without a meal. Follow the directions on the prescription label.

When this medication is used for erection problems, your care team may prescribe it to be taken once daily or as needed. If you are taking the medication as needed, you may be able to have sexual activity 30 minutes after taking it and for up to 36 hours after taking it.

Whether you are taking the medication as needed or once daily, you should not take more than one dose per day. If you think you have taken too much of this medicine, contact a poison control center or emergency room at once.¹²

Tadalafil comes as 2.5 mg, 5 mg, 10 mg and 20 mg tablets.^13,14

The cost will vary based on the strength of the medicine and the amount you are prescribed. But without insurance, tadalafil can cost up to $13 per tablet.¹⁵ RedBox Rx offers tadalafil for as low as $1 per tablet.

Tadalafil is not available over the counter and requires a prescription.¹⁶ Get started with an online consult for erectile dysfunction or premature ejaculation.

Yes, tadalafil can be prescribed for women, particularly to treat certain types of high blood pressure.¹⁷

PDE5 inhibitors such as sildenafil, tadalafil, avanafil and vardenafil all work in the same basic way by relaxing blood vessels to increase blood flow to the penis. They are all effective for treating erectile dysfunction, but they differ mainly in how quickly they start working and how long their effects last.¹⁸

Read our Complete Guide to Compare ED Medications to learn more.

Yes. Check your medication’s bottle for a specific date and always dispose of expired medication.¹⁹

Before taking tadalafil:

• Tell your doctor and pharmacist if you are allergic to tadalafil, any other medications or any of the ingredients in tadalafil tablets. Ask your pharmacist for a list of the ingredients.

• Tell your doctor if you are taking or have recently taken riociguat (Adempas) or nitrates such as isosorbide dinitrate (Isordil), isosorbide mononitrate (Monoket) and nitroglycerin (Minitran, Nitro-Dur, Nitromist, Nitrostat, others). Nitrates come as tablets, sublingual (under the tongue) tablets, sprays, patches, pastes and ointments. Ask your doctor if you are not sure whether any of your medications contain nitrates. Your doctor will probably tell you not to take tadalafil if you are taking nitrates.

• Tell your doctor if you are taking street drugs containing nitrates (“poppers”) such as amyl nitrate, butyl nitrate or nitrite while taking tadalafil. Your doctor will probably tell you not to take tadalafil if you are taking street drugs containing nitrates.

• You should know that tadalafil is available under the brand names Adcirca and Cialis. You should only be treated with one of these products at a time.

• Tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins and nutritional supplements you are taking or plan to take. Be sure to mention any of the following: alpha blockers such as alfuzosin (Uroxatral), doxazosin (Cardura), dutasteride (Avodart, in Jalyn), prazosin (Minipress), silodosin (Rapaflo), tamsulosin (Flomax, in Jalyn) and terazosin; amiodarone (Cordarone, Pacerone); certain antifungals such as fluconazole (Diflucan), griseofulvin (Grifulvin, Gris-PEG), itraconazole (Onmel, Sporanox), ketoconazole (Extina, Ketozole, Nizoral, Xolegel) and voriconazole (Vfend); aprepitant (Emend); bosentan (Tracleer); carbamazepine (Carbatrol, Epitol, Tegretol, Teril, others); clarithromycin (Biaxin, in Prevpac); diltiazem (Cardizem, Cartia,Tiazac, others); efavirenz (Sustiva, in Atripla); erythromycin (E.E.S., E-Mycin, Erythrocin); HIV protease inhibitors, including indinavir (Crixivan), nelfinavir (Viracept), and ritonavir (Norvir, in Kaletra), lovastatin (Altocor, in Advicor); medications for high blood pressure; nefazodone; nevirapine (Viramune); other medications or treatments for erectile dysfunction; other medications or treatments for PAH; phenobarbital; phenytoin (Dilantin, Phenytek); rifabutin (Mycobutin); rifampin (Rifadin, Rimactane, in Rifamate, in Rifater); sertraline (Zoloft); telithromycin (Ketek); and verapamil (Calan, Covera,Verelan, in Tarka). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.

• Tell your doctor what herbal products you are taking, especially St. John's wort.

• Tell your doctor if you smoke; if you have ever had an erection that lasted more than four hours; and if you have recently had diarrhea, vomiting, not been drinking enough fluids or sweating a lot, which may have caused dehydration (loss of a large amount of body fluids). Also tell your doctor if you have or have ever had pulmonary veno-occlusive disease (PVOD; blockage of veins in the lungs); any condition that affects the shape of the penis; diabetes; high cholesterol; high or low blood pressure; irregular heartbeat; a heart attack or heart failure; angina (chest pain); a stroke; ulcers in the stomach; a bleeding disorder; blood circulation problems; blood cell problems such as sickle cell anemia (a disease of the red blood cells), multiple myeloma (cancer of the plasma cells) or leukemia (cancer of the white blood cells); or heart, kidney or liver disease. Also tell your doctor if you or any of your family members have or have ever had an eye disease such as retinitis pigmentosa (an inherited eye condition that causes loss of vision) or if you have ever had sudden severe vision loss, especially if you were told that the vision loss was caused by a blockage of blood flow to the nerves that help you see.

• If you are having surgery, including dental surgery, tell the doctor or dentist that you are taking tadalafil.

• Talk to your doctor about the safe use of alcoholic beverages during your treatment with tadalafil. If you drink a large amount of alcohol (more than five glasses of wine or five shots of whiskey) while you are taking tadalafil you are more likely to experience certain side effects of tadalafil such as dizziness, headache, fast heartbeat and low blood pressure.

• If you are taking tadalafil to treat erectile dysfunction, tell your doctor if you have ever been advised by a healthcare professional to avoid sexual activity for medical reasons or if you have ever experienced chest pain during sexual activity. Sexual activity may be a strain on your heart, especially if you have heart disease. If you experience chest pain, dizziness or nausea during sexual activity, call your doctor immediately or get emergency medical treatment, and avoid sexual activity until your doctor tells you otherwise.

• Tell all your healthcare providers that you are taking tadalafil. If you ever need emergency medical treatment for a heart problem, the healthcare providers who treat you will need to know when you last took tadalafil.²⁰

Talk to your doctor about eating grapefruit and drinking grapefruit juice while taking this medicine, as it may change the amount of medicine that is absorbed by your body.²¹

If you are taking tadalafil for erectile dysfunction on a regular schedule, take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose or more than one dose per day to make up for a missed one.²²

Tadalafil may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• Headache

• Indigestion or heartburn

• Nausea

• Diarrhea

• Flushing

• Pain in the stomach, back, muscles, arms or legs

• Cough

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

• Sudden decrease or loss of vision (see below for more information)

• Blurred vision

• Changes in color vision (seeing a blue tinge on objects or having difficulty telling the difference between blue and green)

• Sudden decrease or loss of hearing (see below for more information)

• Ringing in ears

• Erection that lasts longer than four hours

• Dizziness

• Chest pain

• Hives

• Rash

• Difficulty breathing or swallowing

• Swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles or lower legs

• Blistering or peeling of skin

Some patients experienced a sudden loss of some or all their vision after they took tadalafil or other medications that are similar to tadalafil. The vision loss was permanent in some cases. It is not known if the vision loss was caused by the medication. If you experience a sudden loss of vision while you are taking tadalafil, call your doctor immediately or get emergency medical treatment. Do not take any more doses of tadalafil or similar medications such as sildenafil (Revatio®, Viagra®) or vardenafil (Levitra®) until you talk to your doctor.

Some patients experienced a sudden decrease or loss of hearing after they took tadalafil or other medications that are similar to tadalafil. The hearing loss usually involved only one ear and did not always improve when the medication was stopped. It is not known if the hearing loss was caused by the medication. If you experience a sudden loss of hearing, sometimes with ringing in the ears or dizziness, while you are taking tadalafil, call your doctor immediately. Do not take any more doses of tadalafil or similar medications such as sildenafil (Revatio®, Viagra®) or vardenafil (Levitra®) until you talk to your doctor.

Tadalafil may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).²³

Keep this medication in the container it came in, tightly closed and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children, as many containers (such as weekly pill minders and those for eye drops, creams, patches and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location — one that is out of their sight and reach. Learn more at http://www.upandaway.org.²⁴

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing or can't be awakened, immediately call emergency services at 911.²⁵

Keep all appointments with your doctor.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.²⁶

Brand names for tadalafil are Adcirca® and Cialis®.²⁷

We offer a variety of prescription medication options for premature ejaculation including:

• Sertraline (Generic Zoloft®)

• Paroxetine (Generic Paxil®)

• Cialis®

• Viagra®

• Sildenafil (Generic Viagra®)

• Lidocaine Topical Desensitizing Cream

We offer a variety of prescription medication options for erectile dysfunction including:

• Sildenafil (Generic Viagra®)

• Avanafil (Generic Stendra®)

• Vardenafil (Generic Levitra®)

• Viagra®

• Cialis®

¹ Mayo Clinic

² National Library of Medicine

³ Mayo Clinic

⁴ National Library of Medicine

⁵ Cleveland Clinic

⁶ Mayo Clinic

⁷ Medical News Today

⁸ Cleveland Clinic

⁹ Cleveland Clinic

¹⁰ Cleveland Clinic

¹¹ Cleveland Clinic

¹² Cleveland Clinic

¹³ National Health Service

¹⁴ Drugs.com

¹⁵ Healthline

¹⁶ Mayo Clinic

¹⁶ Mayo Clinic

¹⁸ WebMD

¹⁹ Cleveland Clinic

²⁰ MedlinePlus

²¹ Mayo Clinic

²² Mayo Clinic

²³ MedlinePlus

²⁴ MedlinePlus

²⁵ MedlinePlus

²⁶ MedlinePlus

²⁷ Mayo Clinic